Interpretive Summary: Previous cooperative efforts among scientists from USDA ARS, CMAVE and the University of Florida, Gainesville, led to show that sugar – starch pathway in developing pollen is most susceptible to break down under high temperature stress in maize and sorghum. A continuation of this coop effort has now led to this report that identifies certain specific genes in this pathway, most notably a pollen-specific cell wall invertase that is irreversibly down-regulated in plants exposed to high temperature for short or long term duration. Further characterization and eventual incorporation of such ‘heat-tolerant’ genes will provide superior germplasm that is expected to be better adapted to growth conditions associated with global warming.